"You don't live forever" is a well-worn phrase though one which isn't thought by the emotionally ill for whom daily survival is priority. The unconscious is powerful and prioritizes pain reduction above all else, reality and self-awareness being secondary. Its powerful weapons of anxiety and fear hone and direct behavior at the ignoring of the reality which is obvious to others.
An organized sense of self, sense of who one is, which originates with the childhood experience of a "good-enough" parenting, is needed to experience time passing and wasted years. Like the addict whose world has become reduced to gaining their next "fix" or those surviving a mortal illness, the sensing of time has become absent. Only with greater health can they rejoin the universal human quest for individual fulfillment.